SB 9.13.24
tasmat samarathas tasya
sutah satyarathas tatah
asid upagurus tasmad
upagupto ’gni-sambhavah
Translation by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
The son of Ksemadhi was Samaratha, and his son was Satyaratha. The son of Satyaratha was Upaguru, and the son of Upaguru was Upagupta, a partial expansion of the fire-god.